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CN-122000368-A - Preparation method and application of lithium-carbon dioxide battery anode material

CN122000368ACN 122000368 ACN122000368 ACN 122000368ACN-122000368-A

Abstract

The invention belongs to the field of lithium-carbon dioxide battery electrode materials, and particularly relates to a preparation method and application of a lithium-carbon dioxide battery anode material. The preparation method comprises the steps of (1) immersing a delignified wood matrix in an Sn source solution to obtain a Sn-adsorbed wood matrix, (2) reacting the Sn-adsorbed wood matrix with an Sn source, inorganic alkali and an organic ligand, carrying out solid-liquid separation to obtain Sn-MOF loaded wood, and (3) carbonizing the Sn-MOF loaded wood at 650-750 ℃ in a protective atmosphere. The invention promotes the independent growth of the catalyst particles without overlapping and gives each nanoparticle independent space, reduces aggregation and avoids the deformation and crushing of the particles at high temperature or under the condition of repeated charge and discharge, thereby creating conditions for improving the catalytic performance of the catalyst particles.

Inventors

  • CHENG YUAN
  • LIU RUITAO
  • WANG HAITAO
  • ZHAO JINGBO
  • SUN MAOXIANG
  • WU JIAN
  • Guan Rixin
  • CHEN HAOKAI
  • WANG ZHIFANG
  • Pang Yuxiang
  • Ge Xuanwen
  • He Taonan

Assignees

  • 华能太仓发电有限责任公司
  • 河南许继电力电子有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (10)

  1. 1. The preparation method of the lithium-carbon dioxide battery anode material is characterized by comprising the following steps of: (1) Soaking the lignin-removed wood matrix in a Sn source solution to obtain a Sn-adsorbed wood matrix; (2) Carrying out a reaction between the Sn-adsorbed wood matrix and a Sn source, inorganic alkali and an organic ligand, and carrying out solid-liquid separation to obtain Sn-MOF loaded wood; (3) And carbonizing the Sn-MOF loaded wood at 650-750 ℃ in a protective atmosphere.
  2. 2. The method for producing a positive electrode material for a lithium-carbon dioxide battery according to claim 1, wherein in the step (1), the concentration of Sn in the Sn source solution is 0.15 to 0.35mol/L, and the time for the impregnation is 24 hours or longer.
  3. 3. The method for preparing a positive electrode material of a lithium-carbon dioxide battery according to claim 1, wherein in the step (2), the molar ratio of Sn to inorganic base to organic ligand in the Sn source is 0.015-0.035 mol:2-3 mmol:1.2-1.6 mmol, and the concentration of the organic ligand in the system is 6-8 mmol/L.
  4. 4. The method for preparing a positive electrode material for a lithium-carbon dioxide battery according to claim 3, wherein the Sn source is tin sulfate, the inorganic base is sodium hydroxide, and the organic ligand is terephthalic acid.
  5. 5. The method for preparing a positive electrode material of a lithium-carbon dioxide battery according to any one of claims 1 to 4, wherein the reaction temperature in the step (2) is 50 to 60 ℃ and the time is 3 to 4 hours, and the carbonization time in the step (3) is 2 to 3 hours.
  6. 6. The method for preparing a positive electrode material of a lithium-carbon dioxide battery according to claim 5, wherein the Sn-MOF loaded wood is obtained by performing water washing and freeze drying treatment after solid-liquid separation in the step (2).
  7. 7. The method for preparing the lithium-carbon dioxide battery anode material according to claim 1, wherein the wood substrate in the step (1) is balshawood, and the wood substrate is a sheet with a thickness of 1-2 mm.
  8. 8. The method for preparing a positive electrode material for a lithium-carbon dioxide battery according to claim 1 or 7, wherein the delignifying step (1) comprises placing a wood substrate in a mixed solution of sodium hydroxide and sodium sulfite, performing a first high-temperature treatment at 95 ℃ to 98 ℃, then placing the wood substrate in a hydrogen peroxide solution, performing a second high-temperature treatment at 95 ℃ to 98 ℃, then placing the wood substrate in water for soaking, and then performing freeze drying.
  9. 9. The method for preparing a lithium-carbon dioxide battery positive electrode material according to claim 8, wherein in the mixed solution, the concentration of sodium hydroxide is 2.5-4 mol/L, the concentration of sodium sulfite is 0.4-0.6 mol/L, the first high-temperature treatment time is 3-4 hours, the solubility of the hydrogen peroxide solution is 2.5-3.5 mol/L, the second high-temperature treatment time is 2-3 hours, and the soaking time is more than 12 hours.
  10. 10. Use of the lithium-carbon dioxide battery anode material obtained by the preparation method of any one of claims 1-9 in a lithium-carbon dioxide battery.

Description

Preparation method and application of lithium-carbon dioxide battery anode material Technical Field The invention belongs to the field of lithium-carbon dioxide battery electrode materials, and particularly relates to a preparation method and application of a lithium-carbon dioxide battery anode material. Background The lithium-carbon dioxide battery is one of novel battery systems with ultrahigh energy density, which are developed in recent years, and converts chemical energy into electric energy and supplies power to an external circuit by utilizing the principle that carbon dioxide gas and lithium ions react under the action of a catalyst to generate lithium carbonate and elemental carbon, wherein the generated elemental carbon does not participate in subsequent circulation, so that the lithium-carbon dioxide battery has the dual functions of energy storage and carbon fixation, and is a potential system capable of effectively solving the problems of energy and environment at the same time. Compared with commercial lithium ion batteries, lithium-carbon dioxide batteries have a higher theoretical energy density (1876 wh·kg -1) and theoretical voltage (2.8V vs. Li/Li +), however, a larger voltage difference (typically <2.7V when discharged, >4.2V when charged) between the carbon dioxide reduction reaction and the carbon dioxide release reaction without a catalyst, which easily results in a decrease in energy efficiency, and an excessively high charging potential is liable to cause electrolyte decomposition and electrode oxidation, which in turn limits the development of lithium carbon dioxide batteries. Development of efficient cathode materials is one of the key links to drive the development of lithium-carbon dioxide batteries. At present, carbon nanotubes, graphene, ketjen black, metal Pt, irO 2 and the like are reported to be used as positive electrode materials, but noble metal elements such as Pt, ir and the like belong to rare elements, the cost is high and cannot be used on a large scale, and the materials such as the carbon nanotubes, the graphene and the like have low energy efficiency and serious polarization and cannot be suitable for the use requirement of a lithium-carbon dioxide battery. Disclosure of Invention The invention aims to provide a preparation method of a lithium-carbon dioxide battery anode material, which solves the problems of high charge overpotential, high charge-discharge specific capacity and improved cycle performance of the existing lithium-carbon dioxide battery. The second object of the invention is to provide the application of the lithium-carbon dioxide battery anode material obtained by the preparation method in a lithium-carbon dioxide battery. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The preparation method of the lithium-carbon dioxide battery anode material comprises the following steps: (1) Soaking the lignin-removed wood matrix in a Sn source solution to obtain a Sn-adsorbed wood matrix; (2) Carrying out a reaction between the Sn-adsorbed wood matrix and a Sn source, inorganic alkali and an organic ligand, and carrying out solid-liquid separation to obtain Sn-MOF loaded wood; (3) And carbonizing the Sn-MOF loaded wood at 650-750 ℃ in a protective atmosphere. The invention belongs to the development invention, a natural channel is formed after lignin is removed from a wood substrate, a reaction place can be provided for the generation and decomposition of discharge products, sn can be adsorbed on a plurality of active sites of the wood substrate by soaking, and when Sn-MOF nano particles are synthesized, catalyst particles are promoted to grow independently without overlapping and are given to independent spaces of each nano particle, aggregation is reduced, and deformation and breakage of the particles under high temperature or repeated charge and discharge are avoided, so that conditions are created for the improvement of catalytic performance of the particles. The lithium-carbon dioxide battery charge-discharge experiment shows that the cyclic charge voltage is below 3.8V, the discharge voltage is about 2.8V, the discharge specific capacity is up to 12.86mAh/cm 2, the specific charge capacity is up to 7.27mAh/cm 2, and the cycle times are up to more than 75 times. The battery adopting the lithium-carbon dioxide battery anode material has good performance in the aspects of overpotential, specific charge-discharge capacity and cycle performance. Preferably, in the step (1), the concentration of Sn in the Sn source solution is 0.15 to 0.35mol/L, and the soaking time is 24 hours or more. Vacuum degassing may be assisted during or after impregnation to facilitate gas release within the wood and to facilitate impregnation with the solution. Preferably, in the step (2), the molar ratio of Sn to inorganic base to organic ligand in the Sn source is 0.015-0.035 mol:2-3 mmol:1.2-1.6 mmol, and the concentration of